the air we breathe

>>9010897
>>9010897
Astronauts breathe pure oxygen, but I think the pressure is lower.

>>9010897
>if we lived in a 100% oxygen environment, could we take shallower/fewer breaths per minute and still live?
https://www.quora.com/Why-does-breathing-pure-oxygen-kill-you

>>9010914
>Astronauts breathe pure oxygen
I doubt that

It's true that we only need the oxygen, the other gases don't do anything at their normal athmospheric levels.

Not sure a 100% oxygen athmosphere would allow us to breathe slower since respiratory rate is mostly controlled by carbon dioxide levels in the blood in normal individuals.

>>9010927
In their suits they do. You can use Google you fucking retard.

File: 1491833787896.jpg (342KB, 800x800px) Image search: [Google]

342KB, 800x800px

I imagine the nitrogen is beneficial with biochemical processes, the excess gases are probably pissed out.

>>9010930

I think that the osmotic ability to expire CO2 is the limiting factor in respiration. Excess CO2 is definitely toxic.

>>9010897
if that atmosphere were 100% oxygen everything would be a lot more burny

also we evolved in a 20% oxygen environment so you are kind of confusing cause and effect

>>9010945
>In their suits they do.
So only during spacewalks (and the prep time)
Breathing normal ox/nitro mix more than 99% of the time.

>>9011027

Apollo 1 tested high-pressure pure oxygen cabin atmosphere, which turned out to be a stupid idea as a tiny spark turned the whole thing into an inferno in seconds.

>>9010897
>air is about 79% nitrogen, 20% oxygen, and 1% trace gases. does that mean that over 3/4 of the air we breathe does nothing for us?
If by 'us' you mean human beings, then yes.

>if we lived in a 100% oxygen environment, could we take shallower/fewer breaths per minute and still live?
Yes, but the human race would go extinct in a fairly short amount of time (say 5-10 years) due to oxygen toxicity.

>what about the trace gases, like Ar, Ne, He, etc. do they do anything for us, or could we live without them?
They don't do anything for us.

>would a 100% oxygen atmosphere filter light differently, so maybe the sky would be some color besides blue?
No, blue would still be scattered the most, and thus the sky would continue to be blue.

>also occurs to me a 100% oxygen atmosphere might make fires problematic.
Not really, fires would just be slightly more intense. Oxygen isn't flammable.

100% oxygen allows for the pressure to be lowered whilst keeping the partial pressure of the oxygen the same. It's used in environments that cannot maintain large pressure gradients (but only short term, because long term exposure causes oedema)
It's also used medically to saturate the blood with oxygen, and to treat gangrene caused by anaerobic (oxygen intolerant) bacteria.

>>9011101
>Not really, fires would just be slightly more intense. Oxygen isn't flammable

Excuse me? I think the astronauts of Apollo 1 and every hospital room using oxygen that bars smoking would disagree.

>>9010953
In most cases no. It's just inert. It does mess with combustion sometimes. Specially on uncomplete/abrupt cycles. Which generates NOx and harm the environment.

>>9010897
IIRC in the Early stages of live on earth, the oxygen levels where like 40% and that caused a LOT of problems with the early forests that populated earth, burning everyrhing away. Also. Insects could be MUCH bigger, since they bresthe through small holes like stomas, with a higher oxigen concentration, their breathing did not limit their body sizes as much.

>>9011271
Oxigen isn't flamable anon. But it makes almost anything that contains any kind of stored oxidation chemical energy flamable. Like any hydrocarbon or organic material.

>>9011271
oxygen isnt flammable, it just increases the flammability of other things

>>9011101
>Oxygen toxicity
Why is evolution so retarded?

It's inert, meaning it doesn't react with anything. But what it does do is keep our alveoli from collapsing (called atelectasis). In anesthesia machines, accidents like this are known to occur when you set the FiO2 (inspired oxygen fraction) too high. Because the partial pressure of nitrogen isn't very different in the blood than in the alveoli, it doesn't diffuse into the blood at a large rate keeping the alveoli from collapsing from lack of air. On the other hand, the blood coming from the pulmonary artery is pretty low on oxygen and high on CO2, so the oxygen diffuses quickly into the blood and leaves the alveoli without air, making them collapse and stay shut.

Oh, and it's also toxic to your brain in high concentrations. You know this when you scuba dive under 40 m.

>>9012056
>It's inert, meaning it doesn't react with anything.

That's not really true. Nitrogen is the basis of many compounds like ammonia, cyanide and high-explosives. Nitrogen is also essential to amino acids, nucleic acids and adenosine, and is the fourth most abundant element in your body.

>>9013049
Sorry, I should have been more specific. Nitrogen GAS is inert in the HUMAN BODY. The nitrogen has to be fixed by bacteria out of its super stable diatomic gas before you can do shit with it, in nature that is.

>>9010927
Here I am just landed from a 6hr day into night sortie in a T6 on 100% O2 for half of it.. 100% O2 is used in aircraft all the time. Any time we're expecting to do high g maneuvering or even at altitudes that the cabin alt cant remain under 8000ft we'll chuck the switches up

File: ErnestBorgnine.jpg (485KB, 800x1007px) Image search: [Google]

485KB, 800x1007px

>>9010914
>Astronauts breathe pure oxygen, but I think the pressure is lower.
That's GOT to be wrong.
MY job is tough enough, can you imagine being an astronaut? The pressure must be enormous.

>>9012056
The causes here are completely wrong (and don't make any sense, because O2 is exchanged with CO2; resulting in no net gas volume change). Higher levels of oxygen in the body result in the body being unable to effectively remove reactive oxygen species such as superoxide (O2-). These lead to oxidative stress, with more vascular areas, such as the lungs, having higher levels of these, and so being affected first. This results in inflammation and eventually collapse of the alveoli. This happens over the scale of days (unlike what you described, which would be much quicker).